TLE is a utility for creating, editing and comparing hierarchical data sets such as taxonomies. You can find out more about TLE here.
LegendBurster is an essential tool for working with complex descriptions of complex objects on maps, and for the easy, effective querying of such descriptions. The descriptions may include hierarchical (taxonomic) concepts and attributes, and these are used during query resolution. LegendBurster includes its own copy of the Georeference Online Ltd Ontology Editor. LegendBurster is the first commercial system in the world to provide Semantic Net functionality in a GIS environment. You can find out more about LegendBurster here.